Frequency of tonsilloliths in panoramic views of a selected population in southern iran.

STATEMENT OF THE PROBLEM
Tonsilloliths are relatively common clusters of dystrophic calcified material that form in the tonsillar crypts, mostly the palatine tonsils. Although they may be asymptomatic, some cause halitosis, cough, dysphagia, and foreign body sensation, as well as otalgia. Since tonsilloliths can be detected on panoramic views as radiopaque lesions, and misdiagnosis may lead to wasting time and cost, dentist should be familiar with radiographic characteristics of this type of calcification.


PURPOSE
This study was conducted to determine the prevalence and the pattern of distribution of tonsilloliths on panoramic radiographs.


MATERIALS AND METHOD
This cross-sectional study was based on 2000 panoramic radiographs from 1030 female and 970 male aged 6-75 years old evaluated for the presence and pattern of tonsillolithiasis, between 2011 and 2013 in Shiraz, Iran. Chi-square test and odds ratio were used to evaluate the relationship between tonsillolithiasis and gender. p< 0.05 was considered as statistically significant.


RESULTS
Out of the 2000 individuals, 101 cases (5.05%) had tonsilloliths on panoramic radiographs out of which 61 were male (60.4%) and 40 were female (39.6%), with age range of 18 to 65. Forty patients (39.6%) had both left and right sides involved, 25 of tonsilloliths (24.75%) were located on the right and 36 on the left side (35.65%). Men were more likely to develop tonsilloliths (p= 0.014).


CONCLUSION
Tonsilloliths are not very common finding and can be detected on nearly 5.05% of panoramic radiographs. Most of the cases are unilateral with a diameter less than 2mm.


Introduction
Tonsilloliths, also known as tonsil stones or tonsillar calculi are uncommon calcified structures that develop in enlarged tonsillar crypts, due to a rare form of dystrophic calcification. [1][2] These stones are composed of calcium salts such as hydroxyapatite or calcium carbonate apatite, oxalates, and other magnesium salts and ammonium radicals. They are usually of small sizes and their formation etiology and pathogenesis are unknown.
Some researchers believe that tonsilloliths can be related to lithiasis in other regions of the body. [3] Tonsillar calculi primarily involve the palatine tonsil and may be asymptomatic, hence-they are usually discovered incidentally on panoramic radiographs.
However, non-specific symptoms such as chronic halitosis, foreign body sensation, dysphagia, pain in ear, and or an elongated styloid process could also be suspected. [5][6] Misdiagnosis may impose fear and huge stress on the patient in addition to inappropriate treatments. Having knowledge about the incidence, anatomic location, radiographic appearance, usual size and number of tonsilloliths help save time and cost. Radiographs are the first diagnostic tool in order to detect these radiopaque lesions in the jaws. On panoramic views, tonsillitis appear as single or multiple defined radiopacities on the mandibular ramus, in the region where the dorsal surface of the tongue crosses the ramus in the palatoglossal or glossopharyngeal air spaces ( Figure 1). [4,7] Although these radiopacities are usually seen in a limited area (palatine tonsil), they may be misdiagnosed with other calcified lesions on the image. So, tonsilloliths must be considered as the first differential diagnosis for multiple ill-defined radiopacities detected on the palatal uvula and ramus. [4] Tonsilloliths may be superficially located in tonsillar crypts, seen as a yellowish calcified mass or more deeply located and felt as an enlarged hard lesion. [8] Large-sized tonsilloliths tend to be single while smaller ones are usually multiple. [9] Since they may be present either unilaterally or bilaterally in an image, ghost images should be ruled out in a pano-ramic radiograph. [10] Finally, it is important to note that tonsilloliths rarely complicate the patient's condition; although sporadically, peritonsillar abscess and trismus may appear because of the penetration of tonsillar capsule. [11] In elderly patients, pulmonary complications may be induced secondary to large tonsilloliths aspiration. [1] Some studies demonstrated that tonsilloliths are related to halitosis and tonsillar abscess. [12] Literature review showed that the detection rate of tonsilloliths was under 25%, however some believe otherwise. [13][14] Histological examinations revealed 8% prevalence of these concretions. [4] Babu et al. used panoramic view to present an unusual bilateral and asymptomatic case of tonsilloliths. tonsilloliths. They concluded that tonsilloliths are agerelated but sex-independent. Most of the cases were left sided and 48.9% were bilateral. [17] As mentioned before, tonsilloliths can cause various oral and maxillofacial symptoms which unfortunately some dentists are not familiar with. To the best of authors' knowledge, no epidemiologic study has been conducted on frequency of tonsillolithiasis in this part of the country. This study was aimed to evaluate the preva-Lence and distribution pattern of tonsilloliths on panora-mic views in southern Iran.

Materials and Method
In this cross-sectional study, 2000 panoramic views (1030 female, 970 male, age 6 to 75 years old) of patients referring to a private clinic of maxillofacial radiology, between 2011 and 2013, were retrieved and reevaluated for presence of tonsilloliths.
Panoramic radiographs were acquired using a digital panoramic CRANEX® D SOREDEX device (Finland; 57-85 kVp, 10mA). All panoramic views of acceptable quality were recruited in the study. The presence of tonsillar calculi was evaluated on panoramic radiographs by two calibrated oral radiologists and a post graduate student, using the criteria reported by Ram et al. that mentioned tonsilloliths as radiopaque nodular mass, or masses piled up on the mandibular ramus and soft palate. [12] Unilateral or bilateral occurrence, number, and size of the stones were recorded. The cases with tonsilloliths were divided to subgroups according to both size (less or more than 2 mm) and number (less or more than 5). Since the radiographs had been taken for other dental purposes, no extra dose was exposed to the patients and no name or personal information of patients was recorded in reports and figures, hence, there was no ethical limitation to conduct the study.
Data were described using frequency and percent age. Chi-square test, odds ratio (OR) and 95% confidence interval (95% C.I) were used to assess the relationship between gender and prevalence of tonsilloliths. p< 0.05 was considered statistically significant.

Results
Out of 2000 individuals, 101 (5.05%) were judged to have tonsilloliths on panoramic radiographs (Table 1). The size of stones varied on panoramic radiographs and was less than 2 mm in 66 cases (65.35%) and more than 2mm in 35 cases (34.65%) ( Table 2).
The tonsilloliths were observed in different shapes such as round, oval, and irregular structures.
The number of calcified masses varied from less than 5 in 63 cases (62.38%) to more than 5 in 38 cases   should be considered to explain the discrepancy in rate of tonsilloliths in different studies. If tonsillitis is considered as a major etiology for tonsillolithiasis, the above-mentioned factors will definitely play a role.

Conclusion
The prevalence of tonsilloliths in the studied population was 5.05%. Most of the cases were unilateral with sizes more than 2 mm and number of less than five in an individual.